Internal-combustion engine.



- E. P. DUMANOlS.

INTERNAL COMBUSTION ENEl NE.

APPLICATION FILED MAR. I8. I914.

3 suszTs-suzn 1.

E. P. DUM ANO| S. INTERNAL COMBUSTION ENGINE.

APPLICATION FILED'HARA 1?. 1 914. 7

Patented July 30,1918.

3 SHEETSSHEET 2 I b E w I E. 'P'fDUMANOIS.

INTERNAL COMBUSTION ENGINE.

APPLICATION FILED MAR. 18.1914. v

1 373,834. Patented July 30, 1918 3 SHEETS-SHEET 3.

' the ignition.

EMILE PAUL DUMANGIS, OF PARIS, FE'tANCE.

INTERN L-concussion nivernn.

Specification 0! Letters latent.

Patented July 39, rate.

Application filed March 18, 1914. Serial NO. 825,656. 7

To all whom it may concern:

Be it known that I, EMILE PAUL DUMANOIS, citizen of the French Republic, residing at Paris, Department of the Seine, in France, have invented certain new and useful Improvements in or Relating to Internal-Combustion Engines; and I do hereby declare the following to be a full, clear, and exact description of the invention, such as Will enable others skilled in the art to which it appertains to make and use the same.

The present invention relates to internal combustion engines and more particularly to those in which air is compressed to a high pressure before the injection of the fuel so as to obtain the temperature requisite for In engines of this kind the constructional difficulties are considerable when the bore of the cylinder exceeds cercylinders of different dimensions; the combustion is effected in the smaller cylinder either by self-ignition under a sufficient pressure or through the medium of a spark plug or any other suitable means. As regards the large cylinder it operates either only as an expansion cylinder, with the ex haust. gases of the smaller cylinder or as a combustion and expansion cylinder oythe ignition, with the aid of the gases of the small cylinder, of an explosive mixture the pressure of which cannot exceed a predetermined limit. Such groups or pairs of cylinders may be connected in any numher so as to obtain a predetern'iined total power.

In the accompanying drawing:

Figure 1 shows by way of example, in vertical section a construction of the engine according to the invention and operatingwith self-ignition under pressure;

Fig. 2 is a plan of the device shown in Fig. 1;

Fig. 3 is a vertical section of a modified form of piston in which a valve is employed in the piston for controlling connnunication between the main cylinder and the auxiliary cylinder;

Fig. 4 is a vertical section of an engine similar to that shown in Fig. 1, but operating upon the two-cycle principle;

Fig. 5 is a vertical section of a modified form of engine; 7

Fig. 6 is a plan view of the engine shown Fig. 7 is a vertical section of an engine similar to that shown in Fig. 5, but operating on the two-cycle principle;

Fig. 8 is a vertical section of a modified form of the engine shown in Fig. 5; Fig. 9 is a plan view of the engine shown in Fig.8;

Fig. 10 is a vertical section of a modified form of the engine shown in Fig. 8; and

Fig. 11 is a plan view of the engine shown in Fig. 10. Referring to the drawings, alarge piston 1 (Fig. 1) moves in a cylinder 2 and is provided, at its upper part, with a small piston 3. After a certain period of the con'ipression stroke, the piston 3 engages in the cylinder 4 which is provided above the cylinder 2 thus imprisoning a certain quantity of air w iich is already compressed and heated. The clearance of the cylinder 2 is such, that at the end-of the compression, the pressure obtained is not sufficient to effect. the selfignition; the clearance of the cylinder at is such that the pressure at the end of the compression and therefore the temperature can produce self-ignition of the fuel atomized when the injector valve 5 of the inject-0r 5 -1s opened, with a certain amount of lead or advance. The whole or a portion of the fuel is introduced by injection during the compression stroke, the injection continuing after the upper dead center is reached. The combustion begins in the cylinder at and is COIIIPlQiOd in the cylinder 2 only at the moment the piston 3 leaves the chamber 9% in the case of the construction shown in Fig. 1. If desired, a passage 6 may be provided, which serves to conduct a portion of the injected fuel and ignited gases to the cylinder 2, so as to permit of the creation of predetermined pressures in 4 and in the large cylinder. These openings may be provided with valves, as shown in Fig. 3. In this figure, a sleeve 1 is inserted in the body of the piston to receive a difierem ial piston 1 This differential piston is mounted to slide in the sleeve 1" and is provided with a portion 8 which normally bears against the valve seat 8 formed on the sleeve 1, as clearly shown in the drawing. The valve is normally held closed by a spring R interposed between the lower part of the valve and a plug B screwed into the lower extremity of the sleeve 1. When the pressure in the auxiliary cylinder exceeds that in the main cylinder, by a pretedetermined amount,

opened to establish communicaetu'ccu the two cylinders by means of The combustion therefore in latter at the same time is completed as above described. The duration of the lifting of the injector valve may. be prolonged lJQYl'NlCl the moment when the 119L011 leaves the cylinder 1; even when not injecting fuel, the supplied additional air assists the mixing of the The dollof pistons l and 3 may be obtained means of the usual piston rings. 7 and 8 are suction valves adapted to be controlled simultaneously; 9 and 10 are exhaust valves controlled. in. a simila manner; 11 is the valve servin tor the starting the engine by means of compressed air. The device is also applicable to two-cycle cylinders; as shown in F a. In this case, the exhaust valves 9 and 10 are replaced y an exhaust port 9, so located in the cylinder wall as to be o e.- the piston near the end of its do v: SLI'OkG. This port discharges into an exhaustconduit 10.

Figs. and 6 show a modification in which the small piston is independent of the large one, in the case 01" four-cycle engines. The pistons 12 and 13 are connected to cranks mounted at the-same or approximately the same angl they operate in the c *linders 1 and :tively, the clearances of which are such that at the end of the travel or stroke in 14; t 1P pressure requisite for selfignition is obtained while in 15 a pressure obtained which is below a predetermined llnut. The -iiston 12 may be operated from the connecting rod and crank means.

The operation is as follows:

At end of the common compression stroke. the opera ion of the injector valve 16 the cylinder 1 1 or any other suitable device, etfects the injection of fuel with a certain advance determining ignition in the cf, .der The whole or a portion at the fuel may be intreduced'hy injection during compression. strokl the in lection con- .lnuin after the dead center is reach I Cihe valve 17 or an equivalei'it device, is control ed in such a manner as to open with a suitable delay, into cylinderi i and Though the passage 18, communicates the combustion to the cylinder 15. 1? and by any other 18 mar be realaced. it desiredb one or which may or may not be 'zcl with valves. In the interior of t; c cylinder 5 either the whole of the fuel a portion thereof has been. atomized during the compression stroke. ectiou being adapted to continue dead-point reach-2n and may be t desired 1 i, dispensed with, and the whole tue M1 on as 2 ving shaft like the cylinder by a' may be injected through the injector 16', the gases penetrating under the valve 17 and the passage 18 into the cylinder 15 where the combustion is completed. The cylinder 15 is provided with-an exhaust valve 20 and a suction valve 21 and the cylinder 14 is provided with an exhaust valve 22, the suction taking place through a special valve (not shown) or through the passage 18 and the valve 17. Moreover, if necessary, the valve 22- may be also dispensed with, the valve 17 being then controlled in such a manner as to insure the communication be tween 14 and 15 during the starting of the engine by means of compressed air admit-' exhaust valve 20 is replaced by a port 20 located in the cylinder wall to discharge the exhaust gases into the exhaust conduit 15. Likewise, thesmaller cylinder 14; is pro v-ided with a corresponding port discharging into an exhaust conduit 1 1.

In Figs. 8 to 11, modifications have been shown in which it has been proposed to avoid the high pressure requisite for the self-ignition. The fuel is atomized in the small cylinder during the compression stroke and its ignition is produced at the end of the stroke with a suitable advance, by means of an electric spark plug or any other device usually employed in conjunction with internal combustion engines. The valve between the two cylinders may be eliminated, the two cylinders being thus in constant communication through a passage connecting the two combustion chambers; in this case, the piston of the small cylinder may be dispensed with, and the latter may be suitably formed.

In Figs. 8 and 9, the piston 1 moves in the cylinder 2 munication with the small cylinder 25 through the conduit 26?- 7 and 8 are suction which is in constant com-.

and exhaust valves of the cylinder 2, 27 is air contained in Qfiows through 25, 28 being open at the same time; at the end of the compression stroke ignition is produced in by 29 and the ignited gases produce cona ration in the cylinder 2 in which the role or a portion or" the fuel may have en introduced through 5 during the comssion stroke, the injection continuing, if essary, after the dea.dpoint is reached.

The valve 9 maybe open during the be ginning of the period of compression so as insure a scavenging of 3 through the medium of 2.6. Moreover, if necessary.,'9 may be dispensed With by giving the conduit 26 a suitable section. The device is also applicable to t'svorcycle engines, the "valve 6 being replaced by suitably disposed ports or any other device.

Figs. 10 and 11 show a modification in which the small cylinder is placed above the large one in the case of four-cycle engines. The large piston which moves in the o inder 231, communicates with the small cylinder 32 through one or more orifies 33, is the fuel injector valve or other suitable device; 35 and 36 are the suction and cxhaust valves of 31; Wis the spark plug or an equivalent device; 38'isthe exhaust valve of 32; 39 is the valve for supplying cor. pressed air. v

The operation is-as follows During the compression stroke, the Whole of thefuel or a portion. thereof, is introduced through 34; at the end ofthis stroke the ignition takes place through 3'? with a suitable advance and the ignited gases propagate the conflagration to 33.;

The operation during the expansion, exhaust and suction strokes,'1s the same as'ln the device which forms the object of Figs.

and 2. 38 may be dispensed with, if desired, under the same conditions.

The'operation is similar with two-cycle cylinders, 36 being replaced-by any other with the working cylinder, anda valve positioned in said passage, and operable to open said passage when a predetermined pressure is reached in the auxiliary chamber.

2. In an internal combustion engine, the combination with a Working'cylinder and. its piston, of an auxiliary chamber, an extension on the piston operable in the chamber, an atomizer for injecting fuel into said chamber during the compression period and continuing such injection after the piston reaches the end of its-upward stroke, the clearance between the piston and working cylinder being such that the fuel is not compressed sufi'icientlyto cause self ignition, and

the clearance between the extension'and the auxiliary chamber being such that the fuel is compressed sufficlently to cause self ignition, and means for placing the auxiliary chamber in communication with the working cylinder.

In testimony whereof I aflix my signature,

in presence of two witnesses.

EMILE PAUL DUMANOIS. vVitnosses CHAS. P. PnnssLY, EMILE Kno'rz. 

